This invention relates to arrangements for accessing customer premises equipment using suppressed ringing connection, and more specifically, relates to arrangements for more efficient trunk access from a server to the switches serving the customer premises equipment.
The use of an Intelligent Pathway(trademark) to access customer premises equipment is well known in the prior art. The connection for accessing the equipment is made by suppressing the ringing or other normal alerting signal to the customer so that the customer is not induced to try to answer the call, and that normal terminating features for the customer, such as call forwarding and call waiting are bypassed for this connection. The suppressed ringing connection, also known as an Intelligent Pathway, uses frequency shift keying (FSK), or tone signals to perform an alerting function for the analog or digital customer premises equipment with which it may communicate in either the off-hook or on-hook mode. The communications can be initiated by a server, or can be initiated by the customer premises equipment. In either case, the communication takes place without disturbing the customer or being affected by customer features, over the same loop that is used for customer telephone conversations.
A problem of the prior art is that servers communicate with the switches that are connected to the customers having such customer premises equipment (CPE) over special trunks so that the switches can know from the class of service of the special trunk that connections are to be set up on a suppressed ringing basis. Disadvantageously, this arrangement requires the use of trunks between the server and the each switch serving such CPE.
More broadly, the problem is that a server trunk, i.e., a trunk connecting a server system such as a Utility to a switch, can only be used to access lines connected to that switch, and can only be used for an Intelligent Pathway connection. Further, a suppressed ringing call cannot be forwarded from one switch to another using common inter-office trunks.
The above problem is solved, and an advance is made over the prior art by requiring that the only dedicated trunks be a group of trunks from the server to a convenient switch, and that the character of the requested connection, i.e., the Intelligent Pathway connection, (also known as a suppressed ringing connection), be indicated by a common channel signaling, (CCS7) message identifying a connection from the first switch to any other switch; the connection being made over any available voice trunk to be established as an Intelligent Pathway (suppressed ringing), connection by the terminating switch. The CCS7 message can also convey other suppressed ringing parameters such as an abbreviated ring selection and/or the CPE type. Advantageously, the only dedicated trunks are those between the server and one or more convenient switches. Advantageously, the Public Switched Telephone Network can be used to provide trunks from the initial switch to the switch that serves the CPE. Advantageously, this also removes distance limitations between the server and the CPE, thus permitting one server to serve customers throughout a region, or country; especially, for those cases in which the occupancy of each of the Intelligent Pathway connections is relatively low.
Accordingly, the information received from a server trunk can be combined with the information, (translation information), characterizing the class of service of that trunk, and both can be transmitted over the CCS7 network using an enhanced CCS7 protocol, to a terminating switch serving a line to be accessed from the server trunk. The server trunk is then connected over the Public Switched Telephone Network to that terminating switch, and the server trunk can then access the CPE served by the terminating switch. Advantageously, this arrangement allows a serving trunk to access any type of CPE connected to the Public Switched Telephone Network, provided that the switches use a common signaling protocol, provided that signaling protocol is enhanced to carry the call information, class of service information of the serving trunk and other parameters, and provided that the terminating switch is adapted by program means to accept and process the enhanced signaling protocol.
This arrangement also solves the problem of number portability wherein a customer may move and be served by another switch without changing the directory number of the customer. The CCS7 message can be forwarded to the new switch from the switch receiving the CCS7 message and the trunk connection from the server.
Another method of implementing the link between the Application Controller (Server) and the local serving switch, is to provide a predetermined xe2x80x9cspecialxe2x80x9d dial-in number that activates the suppressed ringing software on the serving switch to provide a suppressed ringing connection for the duration of the call(s). One or more suppressed ringing calls could be placed during one dial-in session. An alternative would require the serving switch to terminate the original call at the special number, and hang up. The switch would place a call back to the Application Controller, thus providing for security while establishing a dedicated Suppressed Ringing call processing activation in the switch. If the security call back were not active, the switch would provide (suppressed ringing) security by looking at the Automatic Number Identification, (ANI) of the incoming call.
This method of communicating with the switch eliminates the requirement that the links from the Controller to its local serving office be dedicated. Therefore, using this method of dialing a xe2x80x9cspecialxe2x80x9d number to activate the feature, permits the links to be dedicated for the duration of the call only.
Another advantage of this method of evoking the Suppressed Ringing feature may be seen if there are no CCS7 trunks to a far office. Using this method, a Controller may dial the xe2x80x9cSpecial Suppressed Ringingxe2x80x9d feature number on the far switch, and communicate directly to the far switch. The far switch is requested by virtue of receiving a call to the xe2x80x9cSpecial Numberxe2x80x9d, to provide the Suppressed Ringing call processing. Either security method could be implemented.
Alternatively, if CCS7 links are not available, the near switch may place a call to the far switch using the xe2x80x9cSpecial Numberxe2x80x9d for Suppressed Ringing, and complete the call without the Controller knowing that the call has been routed in this manner. To accomplish this, the near switch would do a database look-up once it determines that CCS7 trunks are not available. A call is placed to the far end xe2x80x9cSpecial Numberxe2x80x9d and bridged with the original telemetry call.